Locking and unlocking folding brace



LOCKING AND UNLOCKING FOLDING BRACE Filed April 15, i962 @Qin-:HL

ARTHUR z.. S/vo w A TTORA/Y n AL,

United States Patent ftice Patented Dec. 10, 1963 3,113,533 LCKING AND UNLQCKING FTLDiNG Arthur L. Snow, 1403 Cedarhill Drive, Royal Gais, Mich. Filed Apr. 13, 1962, Ser. No. 137,297 1 Claim. (Cl. 16S-134) This invention relates to folding braces and in particular to a folding brace which locks in the supporting position -to prevent accidental :folding of the brace. This prevents accidental collapse of a member supported by the brace.

Various types of folding braces have been employed in the prior art to support a hinged element in a use position and for folding to permit the hinged element to swing to a storage position. However, the several devices of the prior art are complicated in design and construction, expensive to manufacture, and do not lock easily and positively in a support position.

With the foregoing in View, it is a primary `object of the invention to provide a folding brace which is simple in design and construction, inexpensive to manufacture, and which locks easily and posi-tively in the support position.

An object of the invention is to provide a folding brace having pivotally interconnected legs and means preventing the Ilegs pivoting in one angular direction past a straight angle, axially aligned, support position.

An object of the invention is to provide slide means permitting telescopic movement of the legs relative to one another in their supporting position.

An object of the inevntion is to provide selectively operable lock means on the legs to prevent pivoting in the other angular direction locked by inward telescopic movement of the legs and unlocked by outward telescopic movement of the legs.

An #object of the invention is to provide legs U-sha-ped in cross section having web portions and flange portions nesting with one another.

An object of the invention is to provide a pivot pin interconnecting the legs anges in a knee joint.

An object of the invention is to provide an extension on a first or lower leg web portion past the pivot pin contacting the second or upper leg web portion blocking pivoting movement in one angular direction at a straight angle between the legs.

An object of the invention is to provide a cleat on the second leg overlapping the web extension on the rst leg preventing reverse angular movement between the legs from a straight angle thereby locking the legs.

An object of the invention is to provide slots in the anges of one leg at the pivot pin allowing telescopic bidirectional movement betwecn the legs for moving the second leg cleat over the first leg web extension and for moving the cleat from over the extension for respectively locking and unlocking the knee joint.

An object of the invention is to provide nesing attaching plates for the legs to save space and to lend late-ral rigidity.

An object of the invention is to provide a folding brace for a hinged member such as a table which is teles-copically movable to lock by loweringV the member from an elevated position and to unlock by raising the member from a lower position.

A-n object of the invention is to provide an automatically locking folding brace lknee joint which `locks by tirs-t lifting a table to which the brace is attached slightly above a horizontal position and then allowing the table to lower to a horizontal position whereby the one leg cleat moves outside the other leg projection with the upward movement and moves over the projection in the downward movement thereby automatically locking the knee joint.

These .and other obiects of the invention Will become apparent by reference to the following description taken in conjunction with rthe drawing wherein:

FIG. l is a side elevational view of a hinged table and a brace according to the invention lshown in the supporting locked position in solid lines and showing the unlocked and partially yfolded positions in bro-ken lines.

FIG. 2 is a side elevational view of the table and brace of FIG. 1 in the folded position.

FIG. 3 is a partial side eleva-tional view of the brace showing the knee joint in the telescopically extended position; and

FIG. 4 is a cross sectional view of FIG. 1 taken on the l-ine 4 4 thereof.

Referring now to the drawing, the brace shown therein to illustrate the invention comprises a lower leg 10 and van upper leg 111 pivotally interconnected by a pivot pin 12.

Each leg 10' and 1-1 is U-shaped in cross section having a central web and depend-ing anges. The upper leg 11 is narrower than the lower leg 10 and lits inside the lower leg at the pivot pin 112 in nested relationship. The lower leg projects beyond the pivot pin v12 over the upper leg 11 in an extension 14. The web portion of the extension 114 contacts the web portion of the upper leg 111 and prevents angular movement between the legs 1t) and 11 at a straight angle as seen in FIGS. l and 3.

The legs 410 and 1-1 pivot to the folded position of FIG. 2. They unfold from the folded position of FIG. 2 through the position indicated by broken lines in FIG. l to the solid line position .of FIGS. `l and 3. At this point the lower leg 111 extension 14 web portion contacts the web portion of the upper 'leg 1-1 locking the legs against further movement in the unfolding direction.

The pivot pin 12. as shown lies in an aperture formed in the upper leg 11 flanges and i-n slots 15 formed in the lower leg 11th flanges. This permits the upper leg 11 to slide axially relative t-o the lower leg 10. The slots 15 in the lower leg 10l limit upper leg 11 telescopic travel with the pivot pin 12. The upper leg 11 moves telescopically in both directions relative to the lower leg `1() between the position shown in FIG. 3 and the solid line position of FIG. 1.

A tab 16 is xed on lthe upper leg I11 and has an extending cleat 17 lying over the lower leg extension A14 as seen in solid line position of FIG. 1. The lower leg extension 14 lies outside the cleat 17 in the position of FIG. 3. Thus, by telescopically moving Ithe upper leg 11 relative to the lower leg 10, the cleat 17 may be `located over the lower leg extension 1'4 and moved away from the lower leg extension 14 selectively` When the cleat 17 overlies the lower leg extension 14 it locks the legs 10 and 1-1 against pivotal movement in the folding direction. When the upper leg cleat 17 is outside the lower leg extension 14, the legs are free to pivot in the folding direction.

The top end 201 of the upper leg l11 is pivota'lly connected to a plate 21 by a pin 22. The bottom end 23 of the lower leg 10 is pivotally connected to a plate 24 by a pin 25. The plates 21 and 24 are U-shaped i-n cross section and have apertured flanges receiving the pins 22 and 25 respectively. The leg ends 20 and 23 lie within the anges of the plates 21 vand 24 respectively. The plates 21 and 2:4 have web portions equipped with screwreceiving apertures through which screws 26 are inserted.

The plate 21 may be screwed to a table 27 and the plate 24 screwed to a wall or support 2S. A hinge 29 pivotally mounts the table 27 on the support 23. A spacer block 3G may be located between the hinge 29 and the support 28 to space the table 27 outwardly from the support 28 in the folded position, FIG. 2. This creates a parallel space between the table and the support to house the brace between the table and the support in the folded position with the table 217 flying substantially parallel to the support 28.

The brace of the invention is easily mounted by screwing the plate 211 to the table 27 and the plate Z4 to the support 28. In the solid line position of FIG. l, the brace supports the table 27 and is locked against pivotal movement in one direction by the lower leg extension 14 abutting the upper leg r11. In this position the brace is also locked against pivotal movement in the other direction by the cleat 17 overlying the lower leg extension 14.

To collapse the table 27 from the solid line position of FIG. l, the user lifts the table 27 above the solid line position of FIG. 1. This causes the upper leg 111 to move telescopically outwardly of the lower leg 16 with the lower leg ange slots sliding relative to the pivot pin 12. This moves the upper leg cleat 17 from a position over the lower leg extension 14. The user then pushes the brace lknee to broken line position B of FIG. 1 such as with his foot. The user lchen lowers the table to the collapsed position of FIG. 2 with the brace automatically assuming its -folded position.

To erect the table 27, the user elevates the table 27 to the position of FIG. l shown in solid lines whereupon the extension 14 falls on top of the cleat i7. The user then elevates the table 27 above the solid line position indicated in FIG. 1 during which movement the upper leg 11 moves telescopically outwardly from the lower leg 1t) and the lower leg extension 14 falls olf the cleat 17 and drops on the upper leg 11 as shown in FIG. 3. The user then allows the table to descend to the solid line position of FIG. l with the upper leg 11 moving telescopically inwardly on the lower leg '16. This travels the upper leg cleat 17 over -the llower leg extension 14. The brace is now locked against pivoting in either direction as previously described.

The brace of the invention provides means tor supporting a table and for locking the Itable in supported condition against accidental pivoting orf the brace with consequent yaccidental collapse of the table.

The brace of the invention is lockable and unlockable by merely raising and `lowering the table as described without the user being required to reach under the table to operate the locking means.

Two braces according to the invention have been found adequate to support a table thirty inches wide and six-ty inches long. Braces ywith approximately 1% webs and 1/2 flanges made of stock have been found adequate to support such a table with a man sitting on the outer edge.

Braces according to the invent-ion are easy to make, assemble, and mount and are attractive in appearance. When mounted under a table they provide adequate room for persons sitting at the table on chai-rs. Moreover, persons seated at the table cannot accidentally dislodge the braces from'- the supporting position..

Although but a single embodiment of the invention has been disclosed and described in detail, it is obvious that changes may be made in the size, shape, detail, arrangement, and reversal of the various elements of the invention within the scope of the appended claims.

I claim:

A folding brace and hinged table top combination co-mprising a vertical support, a table top adjacent said support, a hinge connecting said support and said table top; said table top being lswingable on said hinge between a use position normal to said support and a storage position substantially parallel to said support,

a base plate secured to said support at a point spaced below said lhinge,

a table plate secured to said table at a point spaced out from said hinge,

a lower leg pivotally connected to said base plate,

an upper leg pivotally connected `to said table plate;

said legs being channels U-shaped in cross section having upwardly disposed webs and depending flanges;

said lower leg having a knee end; said lower leg anges having slots at a point spaced from said knee end of said lower leg; said lower leg thereby having a web extension beyond said iiange slots;

said upper leg having a knee end; said upper leg having aperatures at said knee end of said upper leg,

said lower leg being wider than said upper leg;

said upper leg knee end iitting inside said lower leg knee end with said flanges apertures and slots aligned with one another;

a pivot pin lying in said flanges apertures and slots pivotally interconnecting said legs in a knee joint pivotally movable between a yfolded position of substantially zero angulation to an unfolded straight angle position;

said lower leg web extension beyond said flange slots and pvot pin contacting said upper leg web preventing angular movement between said legs beyond a straight angle in the unfolding direction of angular movement;

said legs pivotally connected 4knee ends when at a straight angle being telesc-opically slidable relative to one another within the limits of said lower leg llange slots sliding relative to said pivot pin between an axially inward weight supporting position and an axially outward non-supporting position;

and a cleat on said upper ieg web extending toward and overlapping said lower leg web projection in the weight supporting position preventing reverse anguilar motion between said legs locking said legs in their straight angle weight supporting position;

axially outward sliding movement of Said legs relative to one another as permitted by said slots at said pin moving said lower leg web projection out of said cleat thereby permitting reverse folding angular movement between said legs from a straight angle to a folded posi-tion of substantially zero degrees;

said legs upon moving ffrom their `folded position to their unfolded straight angle position being blocked from further unfolding motion by said lower leg web projection contacting said upper leg web;

said upper leg web extension being insertable under said cleat by axial outward sliding vmovement between said legs to clear said cleat and subsequent axial inward sliding movement between said legs to move said extension under said cleat;

axial outward sliding unlocking movement being eiected by raising said table at said table plate manually; `axial Iinward sliding movement being effected by releasing said table at said table plate from a manually lifted position.

References Cited in the tile of this patent UNITED STATES PATENTS 376,594 Harter Jan. l7, 1888 408,967 Garretson Aug. 13, 1889 421,384 Casper Feb. 18, 189() 859,454 Larsson July 9, 1907 1,553,047 Kroscliell Sept. 8, 1925 1,724,457 Cummings Aug. 13, 1929 2,483,899 Crasso et al. Oct. 4, 1949 2,843,436 Franks July l5, 1958 

